Mesh shape amended upon undoing in sculpt mode, with Armature & Multires modifiers enabled #76936

New Issue

Baichuan Wu · 2020-05-21T11:09:43+02:00

Baichuan Wu commented

2020-05-21 11:09:43 +02:00

System Information
Operating system: Win10 1909
Graphics card: NVIDIA GeForce GTX 1060

Blender Version
Broken: 2.83
Worked: 2.82

Caused by b2c2d7b7f1

Short description of error
With Armature & Multires modifiers enabled, upon undoing in sculpt mode, armature deformation to the mesh is incorrectly applied.
multires_armature_sculpting_undo_bug.mp4

Exact steps for others to reproduce the error
#76936.blend

Open file
Change pose
Go to sculpt mode
Sculpt
Undo
Go to object mode

**System Information** Operating system: Win10 1909 Graphics card: NVIDIA GeForce GTX 1060 **Blender Version** Broken: 2.83 Worked: 2.82 Caused by b2c2d7b7f1 **Short description of error** With Armature & Multires modifiers enabled, upon undoing in sculpt mode, armature deformation to the mesh is incorrectly applied. [multires_armature_sculpting_undo_bug.mp4](https://archive.blender.org/developer/F8546177/multires_armature_sculpting_undo_bug.mp4) **Exact steps for others to reproduce the error** [#76936.blend](https://archive.blender.org/developer/F8552641/T76936.blend) - Open file - Change pose - Go to sculpt mode - Sculpt - Undo - Go to object mode

Baichuan Wu commented

2020-05-21 11:09:43 +02:00

Added subscriber: @EwKY

blender-admin commented

2020-05-21 11:09:43 +02:00

#84561 was marked as duplicate of this issue

Germano Cavalcante commented

2020-05-22 14:58:37 +02:00

Added subscriber: @mano-wii

Germano Cavalcante commented

2020-05-22 14:58:37 +02:00

Could you provide a simple .blend file showing the problem?

Baichuan Wu commented

2020-05-24 10:04:10 +02:00

Absolutely!

Here are two .blend files demonstrating the setup for reproducing the error in v2.83 and v2.90, alongside a detailed video demo, please pitch me in if you need further clarification for reproduction!

BUGreportvideo.mp4
BUGreportfile(2.90).blend

BUGreportfile(2.83).blend

Bests

Absolutely! Here are two .blend files demonstrating the setup for reproducing the error in v2.83 and v2.90, alongside a detailed video demo, please pitch me in if you need further clarification for reproduction! [BUGreportvideo.mp4](https://archive.blender.org/developer/F8550464/BUGreportvideo.mp4) [BUGreportfile(2.90).blend](https://archive.blender.org/developer/F8550471/BUGreportfile_2.90_.blend) [BUGreportfile(2.83).blend](https://archive.blender.org/developer/F8550468/BUGreportfile_2.83_.blend) Bests

Richard Antalik commented

2020-05-25 12:23:21 +02:00

Changed status from 'Needs Triage' to: 'Confirmed'

Matt Starsoneck commented

2020-08-12 09:14:50 +02:00

Added subscriber: @matt.starsoneck

Steffen Hartmann commented

2020-10-22 17:33:07 +02:00

Added subscriber: @Harti

Steffen Hartmann commented

2020-10-22 17:33:07 +02:00

I can confirm this bug. Tested with 2.90 and 2.91 beta.
It seems the main problem is going outside of sculpt mode after sculpting on the mesh. The armature modifier is broken afterwards and complety destroys the mesh.

In my opinion this is a highly critical bug.

I can confirm this bug. Tested with 2.90 and 2.91 beta. It seems the main problem is going outside of sculpt mode after sculpting on the mesh. The armature modifier is broken afterwards and complety destroys the mesh. In my opinion this is a highly critical bug.

Philipp Oeser commented

2021-01-19 14:00:13 +01:00

Added subscribers: @Diogo_Valadares, @lichtwerk

Diogo Valadares Reis dos Santos commented

2021-01-19 14:14:35 +01:00

well, it has been in blender for a while, I also think this needs a bit more attention

Philipp Oeser commented

2021-01-19 14:22:41 +01:00

Bisecting this as we speak

Philipp Oeser commented

2021-01-19 17:21:08 +01:00

Added subscriber: @Sergey

Philipp Oeser commented

2021-01-19 17:21:08 +01:00

Caused by b2c2d7b7f1

@Sergey: Interested?

Caused by b2c2d7b7f1 @Sergey: Interested?

Sergey Sharybin self-assigned this 2021-01-19 18:12:49 +01:00

Sergey Sharybin commented

2021-01-19 18:12:49 +01:00

I will have a look here.

The issue here is that Apply Base will refine OpenSubdiv descriptor to the new state, and undo needs to refine it back to the old coordinates, without doing full object re-evaluation (because otherwise sculpted data is lost). So, the idea is simple: get access to the proper base mesh coordinates, without evaluating dependency graph.

Something like this should work P1896.

It does perform mesh evaluation, but is temporal and hence does not affect the state of the sculpt session. Alternative would be to store subdiv base coordinates in the undo geometry node, but this would be extra memory usage for no real immediate benefit.

Running out of time today, tomorrow will submit a proper review and ask for an intense testing.

I will have a look here. The issue here is that Apply Base will refine OpenSubdiv descriptor to the new state, and undo needs to refine it back to the old coordinates, without doing full object re-evaluation (because otherwise sculpted data is lost). So, the idea is simple: get access to the proper base mesh coordinates, without evaluating dependency graph. Something like this should work [P1896](https://archive.blender.org/developer/P1896.txt). It does perform mesh evaluation, but is temporal and hence does not affect the state of the sculpt session. Alternative would be to store subdiv base coordinates in the undo geometry node, but this would be extra memory usage for no real immediate benefit. Running out of time today, tomorrow will submit a proper review and ask for an intense testing.

blender-admin commented

2021-01-20 12:13:48 +01:00

This issue was referenced by 2ba2d2bd9d

This issue was referenced by 2ba2d2bd9ded9b944ff94894bc09d695cdb5bae0

Sergey Sharybin commented

2021-01-22 12:26:32 +01:00

Changed status from 'Confirmed' to: 'Resolved'

Sergey Sharybin closed this issue

2021-01-22 12:26:32 +01:00

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Mesh shape amended upon undoing in sculpt mode, with Armature & Multires modifiers enabled #76936